Rainer Horstmann has a dream: in this era dominated by CDs and MP3s he wants to build the best record deck the world has ever seen. When all is said and done, audio experts and fans of vinyl all agree on this one point: the good old record is head and shoulders above the rest in terms of reproduction quality and fullness of tone. This is confirmed by record sales, which are now doubling year on year. Horstmann is the founder and managing director of AVDesignHaus, a professional sound engineering, film production and media management agency. His mantra for developing his record deck is simplicity itself: No Compromise. In his flagship phono unit, the Dereneville VPM 2010-1, he uses only the highest-quality, state-of-the-art components.
Tangential linear unit with stepper motor
What sets the Dereneville apart from other decks is its tangential drive, which operates with the utmost precision. "It senses the record groove in exactly the same way as it was cut into the vinyl by the groove cutting machine", explains Horstmann. This enables his phono machine to reduce the maximum tracking angle error to as little as 0.02°, thereby achieving unparalleled sound quality. In conventional record decks, for the purpose of comparison, the angle error will be up to 2°. "What's more", continues our audio-visual expert, "this can be heard very clearly as distortion in the trebles or as stereo channel offset".
The heart of the deck is formed by a linear unit that constantly guides the gimbal-bearing tonearm towards the centre of the record. A laser system, which is likewise adjusted by two linear controllers, continuously checks that the arm maintains a tangential angle of 90° to the groove and also continuously sends its measured values on to the electronic control unit. This unit works in steps that are subdivided into 256 micro steps to control the forward movement of the linear unit. The unit's drive is configured for 800 steps for each revolution. In theory, therefore , the smallest possible movement of the linear unit equates to 0.000024 millimetres.
Linear technology produced in Minden
These ultra-precision linear controllers are manufactured and supplied by the Minden-based company Rose+Krieger (RK). This company supplies a comprehensive range of linear components and profile, joining- and modular technology. Rose+Krieger develops and produces components and system solutions for virtually every sector of industry, but first and foremost for mechanical engineering. "For our linear controllers to be used in record decks is nonetheless a first for us" observes Bernd Klöpper, the marketing manager at RK.
Horstmann himself describes the RK linear units as most attractively designed, but the main reason behind his decision to use them is their outstanding precision. A circular ball-bearing guideway and a ball-screw spindle with zero play ensure the degree of precision that he is striving for in the Dereneville. Furthermore, in order to control the tonearm he needed a special length with a travel of just 160 millimetres and a short overall length of 368 millimetres. Rainer Horstmann found it extremely difficult to find a supplier in the market who could produce a unit to such specifications. The Minden-based specialists supplied Horstmann with a custom-built unit based on the RK DuoLine 50. The most significant difference between this unit and the standard model is its unusually small spindle pitch of 12 x 5 mm (standard pitch is 12 x 10 mm). "This was the only way in which we could produce the drive that Herr Horstmann wanted, which would run extremely slowly and with total precision", explains RK's project manager Olaf Durstewitz.
Special commissions are nothing out of the ordinary
For the linear technology professionals at RK Rose+Krieger this kind of custom commission is an everyday situation. "We specialise in small-batch manufacturing to the customer's specifications and to tight deadlines", says Bernd Klöpper. "Customer- and application-specific jobs are our bread and butter." Rose+Krieger accordingly got to grips with Horstmann's problem rapidly, and within four weeks they were able to deliver the required product.
In addition to the custom-built unit, Rainer Horstmann has also integrated two other RK linear controllers in his Dereneville: these are two RK Compact 30/89s with a travel of 30 millimetres, and are used for fine adjustment of the tonearm, thus enabling the VTA (vertical tracking angle) to be adjusted and also enabling tonearms of differing lengths to be used. These "stock items" were in the hands of the customer just a few days after the order was received.
Expensive hobby
The target group for a Horstmann record deck consists exclusively of extremely well-heeled individuals with a penchant for vinyl, and for whom nothing but the best will do. This remarkable piece of kit is not exactly a snip. Hi-fi fans will need deep pockets to pay for this unique sound quality and precision - the Dereneville VPM 2010-1 has a price tag of around 500,000 euros. It is manufactured purely to order. And some prospective buyers have already come forward. "A customer from southern Germany wants to visit us and talk to us with a view to purchasing, we've received a second serious enquiry from Dubai and another one from Japan", says Rainer Horstmann. A well-known dealer from the United States would like to exhibit the Dereneville at the forthcoming CES trade fair in Las Vegas and has invited Horstmann to join him there. Visitors to that fair will then have the opportunity to be won over by the unique quality of the Dereneville. The precision linear units produced by Rose+Krieger in Minden play their part in this top-quality product.
